Drilling apparatus with down-the-hole motor

ABSTRACT

The apparatus includes a piston-like means having a hammer mechanism thereon and an elongated excavation means suspended from the piston-like means. It also includes a rotary drill rod comprising an elongated pipe having a longitudinally extending bore therethrough and an annular bit at the distal end thereof. The piston-like means is slidably received in the bore of the pipe through the proximal end thereof, and there is an annular shoulder about the periphery of the bore to receive blows from the hammer of the mechanism adjacent the bit. Also, means define an annular seat about the periphery of the bore between the shoulder and the mouth of the bit, which is of lesser inside diameter than that of the shoulder. The excavation means is slidably received in the distal end portion of the bore through the opening of the shoulder and has one end thereof engaged with the seat. In addition, fluid passage means in the rod extend generally longitudinally of the bore between a point adjacent the shoulder and a point about the periphery of the seat, and porting in the body of the bit, extends generally axially thereof between the fluid passage means and the working face of the bit at the distal end thereof. Together, the fluid passage means and the porting form a passage about the excavation means through which fluid can be released into the working face of the bit from a point adjacent the opposite end of the excavation means. There are also means whereby the released fluid can discharge from the face of the bit toward the proximal end of the pipe on the opposite side of the pipe from the excavation means.

Sept. 9, 1975 DRILLING APPARATUS WITH DOWN-THE-HOLE MOTOR hammer mechanism thereon and an elongated excavation means suspended from the piston-like means. It

also includes a rotary drill rod comprising an elon gated pipe having a longitudinally extending bore therethrough and an annular bit at the distal end in nt r: Gerald T. Sweeney, Federal Way,

Wash.

| ftwinncu; we 'n he p u w thereof. The piston like means is slidably received in the bore of the pipe through the proximal end thereof,

June 1 [974 l Filcll' and there is an annular shoulder about the periphery of the bore to receive blows from the hammer of the mechanism adjacent the bit. Also, means define an an- AnplNo 475.594

Related .5. Application Data nular seat about the periphery of the bore between the shoulder and the mouth of the bit, which is of lesser inside diameter than that of the shoulder.

m ll of Sci" No.

The excavation means is slidably received in the distal end por- 175/24 tion of the bore through the opening of the shoulder E213 and has one end thereof engaged with the seat. in ad l75/58, 92, 105, 236,

Field of Search dition, fluid passage means in the rod extend generally 7!, e shoulder and a point about the periphery of the seat, and porting in the body of the bit, extends generlfiol References Cited ally axially thereof between the fluid passage means UNl'l FD STATES PATENTS and the working face of the hit at the distal end thereof, Together immons l75/105 [he fluid PASS-Age means the porting form a passage about the excavation means (O2 33 H5 57 t through which fluid can be released into the working face of the bit from a point adjacent the opposite end of the excavation means There are also means whereby the released fluid can discharge from the face of the bit toward the proximal end of the pipe on the opposite side of the pipe from the excavation means.

Irmm t l-kummcr james A. Leppink [7 Claims. 5 Drawing Figures [5 7] ABSTRACT The apparatus includes a piston-like means having a PATENTEDSEP 19 SHIET 2 OF 2 HIM DRILLING APPARATUS WITH DOWN-THE-HOLE MOTOR This is a divisional of application Ser. No. 283.208.

filed Aug. 23. 1972 and now U.S. Pat. No. 3.854.539.

THE INVENTION IN GENERAL According to the invention. the apparatus includes a pistonlike means having a hammer mechanism thereon and an elongated excavation means suspended from the pistonlike means. It also includes a rotary drill rod comprising an elongated pipe having a longitudinally extending bore therethrough and an annular bit at the distal end thereof. The piston-like means is slidably received in the bore of the pipe through the proximal end thereof, and there is an annular shoulder about the periphery of the bore to receive blows from the hammer of the mechanism adjacent the bit. Also. means define an annular seat about the periphery of the bore between the shoulder and the mouth of the bit. which is of lesser inside diameter than that of the shoul der. The excavation means is slidably received in the distal end portion of the bore through the opening of the shoulder and has one end thereof engaged with the seat. In addition. fluid passage means in the rod extend generally longitudinally of the bore between a point adjacent the shoulder and a point about the periphery of the seat. and porting in the body of the bit. extends generally axially thereof between the fluid passage means and the working face of the bit at the distal end thereof. Together. the fluid passage means and the porting form a passage about the excavation means through which fluid can be released into the working face of the bit from a point adjacent the opposite end of the excavation means. There are also means whereby the released fluid can discharge from the face of the bit toward the proximal end of the pipe on the opposite side of the pipe from the excavation means.

The shoulder may be disposed in the pipe and the excavation means may take the form of a core barrel. Also. the fluid passage means may take the form of fluting in the peripheral wall of the bore.

In certain ofthe presently preferred embodiments of the invention, the hammer mechanism is fluid operated and there are fluid transmission means for operating the hammer mechanism including means for passing fluid through the pistonlike means and means for exhausting the fluid into the fluid passage means after the mechanism has operated. Also, in these embodiments. the invention further comprises means on the pistonlike means for generating a pressure differential thereacross longitudinally of the bore. to maintain the hammer mechanism in operative relationship to the shoulder during the application of the blows. In one embodiment. for example. the proximal end portion of the bore is operatively fluid pressurized and the pressure differential generating means is operative to cause a pressure drop across the piston-like means in the direction of the distal end of the bore.

In these presently preferred embodiments. moreover, the piston-like means has an anvil suspended therefrom. and the anvil is interposed in the bore between the hammer and the shoulder to receive and transmit the blows to the shoulder. The excavation means is suspended in turn from the anvil and is axially and/or rotationally displaceable in relation to the anvil. Where the hammer mechanism is fluid operated and there are fluid transmission means for operating the hammer mechanism including means for passing fluid through the piston-like means and means for exhausting the fluid into the fluid passage means after the mechanism has operated. the anvil may define a passage for the fluid and the fluid exhaust means may be operative to exhaust the fluid through the anvil passage.

In the presently preferred embodiments. moreover, the bit has a greater diameter than the pipe. and the pipe forms the inner periphery of an annulus which is disposed between the pipe and the wall of the excavated hole. to discharge the released fluid there through. For example, the outer periphery of the bit may be adapted so that the released fluid can pass thereacross to an annulus formed by the pipe and the wall of the excavated hole.

The bit may be rigidly connected to the distal end of the pipe.

Also. the invention may further comprise attachment means on the proximal end of the piston-like means for releasable engagement by a wire line retriever or the like.

The excavation means may be relatively rotatably engaged with the seat; and may be axially displaceable in relation to the piston-like means and yieldably biased into a stopped position relatively spaced therefrom.

FIG. I is a part longitudinal cross-sectional view of one of my presently preferred embodiments of the invention. as it is seen in use for a dowmthe-hole core drilling operation. and with the hammer mechanism in the bottomed condition thereof;

FIG. 2 is another such view as the hammer mechanism is in the upstroke thereof;

FIG. 3 is a transverse cross-sectional view along the line 3-3 of FIG. 1;

FIG. 4 is another part longitudinal cross-sectional view when the drive means has been retracted from the drill rod; and

FIG. 5 is a part perspective view of the bit employed in the drill rod.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, it will be seen that the drill rod comprises an elongated. fluid pressurized pipe 2, which is assembled from equal-diameter sections that are perhaps 10' in length and threaded and flushcoupled to one another as illustrated. With the exception of the interior of the bottommost or distal end section 2 of the pipe, the sections are otherwise similar to one another, and are added to and subtracted from the pipe as is necessary during the drilling operation. The distal end section 2' differs. however, in that it has a stepped or counterbored interior configuration which forms an inner peripheral shoulder 3 at a point near the top thereof. The shoulder serves as an abutment for the drive means 4, which is retractable from the red. as shall be explained; and which includes a standard. fluid-operated down-the-hole hammer mechanism 5.

The pipe is pressurized and driven by a conventional drilling mechanism, such as that shown in U.S. Pat. No. 339L543, and is typically driven at slow speeds such as 10 RPM, that is. at speeds simply sufficient to index the percussion bit 7 seen at the bottom or distal end of the pipe. The bit 7 is annular in configuration. and has an interiorly threaded collar 8 at the upper end thereof. that flushcouples to the distal end section 2' of the pipe. Below the collar, however, the bit is flared radi ally outwardly and forms an enlarged head which terminates with a flatfaced annulus 12 at the working end thereof. The annulus has sets of button-like percussion points 14 seated in raised condition thereon, which are spaced apart in angularly spaced, clockwise, convolutional lines that are symmetrically arranged about the axis of the bit. See FIG, 5. In addition, the endmost points 14 on each line, are seated in the head so as to project slightly inside and outside of the inner and outer peripheries of the annulus, respectively. As a consequence, when the rod is rotated and hammered into an earth formation l6, the bit excavates an annular recess the outside diameter of which is not only greater than the outside diameter of the pipe itself, but also greater than the outside diameter of the flared head 10 of the bit. Likewise, the core 18 of earth material which is captured within the end of the rod, has an outside diameter of slightly lesser dimension than the inside diameter of the head of the bit.

Otherwise, the bit has a stepped or counterbored interior Configuration forming an annular shoulder 20 inside of and about the bottom end of the collar 8. The interior of the bit also has another annular shoulder 22 therebelow, which is of lesser inside and outside dimen sions than the shoulder 20, by virtue of there being an inwardly chamfered surface 24 at the bottom of the cylindrical socket 26 separating the two shoulders. The lower shoulder 22 and the socket 26 form a seat for a core barreling tube 40 on the drive means, as shall be explained; whereas the upper shoulder 20 has an annular groove 30 recessed therein, from which a series of symmetrically angularly spaced ports 32 open through the body of the head 10 to the working face 12 of the bit, between the points 14 thereon. The ports are also canted to the axis of the head, and are so angled into the shoulder that they open into the socket 26.

During the drilling operation, the compressed fluid is intermittently discharged to the ports 32 to flush the removed earth material back through the clearance 34 between the pipe 2 and the wall of the excavation. The fluid reaches the ports through a series of passages 36 which are formed within the drive means and the distal end section 2' of the pipe, as shall be explained more fully hereinafter.

The drive means 4 also includes an annular anvil 38 which is slidably engageable in the upper, thinner walled portion of the distal end section 2', and sized to seat on the shoulder 3. The core barreling tube 40 is slidably engageable in the bore 42 of the lower, thicker walled portion of the section 2', and suspended from the anvil to seat relatively rotatably within the socket 26 of the bit. The tube is equipped with a bushed, ball bearing mounted swivel head 44 on the upper end thereof. and the bushing 46 of the head is slidably engaged on, but rotationally keyed to a flanged swivel pin 48, which is fastened upright to the underside of the anvil. Moreover the kcyway 50 for the bushing, and the length of the bushing, are sized in relation to the pin, to allow for play between the tube and the anvil, axially thereof; and a coiled spring 52 is interposed about the bushing 46, between the head and the underside of the anvil, to bias the tube in the downward direction,

toward the flange 48 of the pin. Thus, when the drive 6 displacement in relation to the anvil, where there is earth material lodged within the bit. The earth material may be dislodged, however, either by the anvil. or by the fluid discharge, or by both, as shall be explained hereinafter.

In addition to being adapted to mate with the bit, the forward end portion 40 of the tube 40 is also adapted to lift or separate the core 18 from the earth formation when the drive means 4 is retracted from the bore of the pipe. The tube 40 is formed in two threaded and flushed-coupled parts, the more forward 40 of which is chamfered at the end, so as to mate with the chamfercd socket 26 of the bit, and form an essentially air tight joint therebetween. The more forward portion 40 also has an upwardly and outwardly tapered surface 54 formed between the cylindrical mouth 56 and the threaded collar 58 of the same; and when the two parts of the tube are assembled, a tapered wedge-like annular core lifter 60 is inserted within the more forward portion, to perform the core lifting and separating function in conventional fashion.

The outer cylindrical surface 62 of the anvil is closely machined to form a fluid seal with the bore of the pipe. Above the surface, however, the anvil is swaged inwardly and provided with a filleted shoulder 64 thereabout, from which a nipple-like shank or cmbossment 66 is upstanding on the axis of the anvil, and equipped with a wide circumferential groove 68 thereabout. The bore 70 of the anvil is counterbored from above and below, and the upper counterbore 72 of the same is adapted to interengage with the hammer mechanism, as shall be explained, whereas the lower counterbore 74 provides a socket for the swivel pin 48, which is secured in the socket by means of a dowel 76.

The hammer mechanism 5 is a modified version of a standard down-the-hole air hammer mechanism, comprising an outer tubular casing 78 having a pipe hammer 80 reciprocably engaged about a stationary control rod 82 therein. The control rod 82 is ported and infrastructured to enable the compressed fluid to reciprocate the hammer in known manner, and alternately to ex haust through porting 84 in the distal end 86 of the control rod. The fluid enters the control rod through a port or ports in a spear-headed, piston-like cap 88 which is threaded onto the upper end of the casing and adapted to slidably engage with the wall of the bore of the pipe 2, as illustrated. The ports 90 are equipped with spring-loaded throttle valves 92 that operate to produce a pressure drop between the upper and lower sides of the drive means, so that the fluid can assist in seating the anvil on the shoulder 3 of the pipe.

The anvil is coupled to the hammer mechanism by telescopically engaging a threaded, two-part, inner ribbed collar 98 about the cmbossment 66 of the anvil 38, and flush-coupling the collar to the distal end of the casing 78, the inner circumferential rih 100 of the collar, meanwhile interengaging in the groove 68 of the cmbossment. The drive means is retracted from the rod by an overhead hoist, such as a standard wire-line re tricvcr, the dogs 96 of which are engaged about the spearhead 94 of the cap.

During the drilling operation, the hammer 80 interfaces with the annulus l02 at the upper end of the anvil, and applies intermittent blows to the anvil, as the pipe 2 is rotated thereaboutv Thus, the bit is continually advanced in the axial direction by the percussive effect of the hammer, and at the same time, is continually rotated by the pipe, so that the points 14 of the bit are reindexed with respect to the face of the excavation, each time that the hammer strikes. Moreover, due to the telescoping relationship between the tube 40 and the pipe, and the relatively reciproeable, swiveled relationship between the tube and the anvil, the tube remains substantially stationary with respect to the pipe, as the pipe is rotated and advanced into the formation.

During the drilling operation, moreover, the exhaust porting 84 in the control rod is placed in communication with the passages 36, so as to exhaust the fluid about the bit. As seen, the distal end portion 86 of the control rod is slidably inserted in the bore 72 of the an vil; and in the bore, there is a series of symmetrically angularly spaced and outwardly slanted ports 104, which open to the underside of the anvil, opposite the chamber 106 which is formed between the head 44 of the tube and the anvil. From there, the fluid enters a serics of symetrically angularly spaced flutes 108 in the bore 42 of the pipe, which commence below the level of the shoulder 3, and terminate in the distal end of the pipe, to communicate with the groove 30 and the ports 32 in the bit. In the engaged and socketed condition of the tube 40. the open sides of the flutes are closed by the main body of the tube. and the socket 26 is occupied by the forward portion 40' thereof. so that the fluid can escape only through the ports 32. Until the tube is socketed in the bit, however, a portion of the fluid will discharge through the axial opening of the bit, so as to assist in flushing out any accumulated debris which would otherwise prevent the tube from seating in the socket of the bit.

Moreover, in such a case, the spring 52 will be compressed by the tube to the point where the bushing 46 of the swivel head engages the face of the anvil; and thereafter, when the hammer 80 is applied to the anvil, the force of the hammer will operate on the tube only, until the anvil re engages the shoulder 3 of the pipe. Thus, the operator can be assured that the tube will be properly seated before the drilling operation is begun.

In the seating process, moreover, a passage 110 through the pin 48, assures that the tube 40 is also pressurized, so that the debris can move only in the direction outward through the clearance 34.

Of course, as drilling progresses, more and more sections are added to the drill pipe 2. If necessary or desired, the tube can be changed at the same time to account for wear of the inner points of the bit; or the bit can be changed; or both can be changed.

For overhead or sidewall drilling, the fluid may also be employed as a means of seating the drive means; as for example, where the drive means is run into the rod at a pressure below that at which the valves 92 open, and then the pressure is raised to open the valves and commence drilling.

Where it is desired to drill for a period without cor ing, a plug-like bit can be substituted for the core bar reling tube. and interengaged either with the pipe or with the annular bit, to rotate conjointly with the same.

I claim:

1. ln combination, a piston-like means having a barn mer mechanism thereon. an elongated excavation means suspended from the piston-like means, a rotary drill rod comprising an elongated pipe having a longitudinally extending bore therethrough and an annular bit at the distal end thereof, the piston-like means being slidably received in the bore through the proximal end thereof and there being an annular shoulder about the periphery of the bore to receive blows from the hammer of the mechanism adjacent the bit, means defining an annular seat about the periphery of the bore between the shoulder and the mouth of the bit, which is of lesser inside diameter than that of the shoulder, the excavation means being slidably received in the distal end portion of the bore through the opening of the shoulder and having one end thereof engaged with the seat, fluid passage means in the rod extending generally longitudinally of the bore between a point adjacent the shoulder and a point about the periphery of the seat, and porting in the body of the bit, extending generally axially thereof between the fluid passage means and the working face of the bit at the distal end thereof, together forming a passage about the excavation means through which fluid can be released into the working face of the bit from a point adjacent the opposite end of the axcavation means, and means whereby the released fluid can discharge from the face of the bit toward the proximal end of the pipe on the opposite side of the pipe from the excavation means.

2. The combination according to claim 1 wherein the shoulder is disposed on the pipe.

3. The combination according to claim I wherein the excavation means takes the form of a core barrel.

4. The combination according to claim I wherein the fluid passage means takes the form of fluting in the peripheral wall of the bore.

5. The combination according to claim I wherein the bit is rigidly connected to the distal end of the pipe.

6. The combination according to claim 1 further comprising attachment means on the proximal end of the piston-like means for releaseable engagement by a wire-line retriever or the like.

7. The combination according to claim 1 wherein the excavation means is relatively rotatably engaged with the seat.

8. The combination according to claim 1 wherein the excavation means is axially displaceable in relation to the piston-like means and yieldably biased into a stopped position relatively spaced therefrom.

9. The combination according to claim 1 wherein the bit has a greater diameter than the pipe and the pipe forms the inner periphery of an annulus which is disposed between the pipe and the wall of the excavated hole, to discharge the released fluid therethrough.

10. The combination according to claim 9 wherein the outer periphery of the bit is adapted so that the released fluid can pass thereacross to an annulus formed by the pipe and the wall of the excavated hole.

11. The combination according to claim 1 wherein the hammer mechanism is fluid operated and there are fluid transmission means for operating the hammer mechanism including means for passing fluid through the piston-like means and means for exhausting the fluid into the fluid passage means after the mechanism has operated.

12. The combination according to claim ll further comprising means on the piston-like means for generating a pressure differential thcreacross longitudinally of the bore, to maintain the hammer mechanism in operativc relationship to the shoulder during the application of the blows.

13. The combination according to claim 12 wherein the proximal end portion of the bore is operatively fluid pressurized and the pressure differential generating placeahle in relation to the anvil.

17. The combination according to claim 14 wherein the hammer mechanism is fluid operated and there are fluid transmission means for operating the hammer mechanism including means for passing fluid through the piston-like means and means for exhausting the fluid into the fluid passage means after the mechanism has operated. and wherein the anvil defines a passage for the fluid and the fluid exhaust means is operative to exhaust the fluid through the anvil passage. 

1. In combination, a piston-like means having a hammer mechanism thereon, an elongated excavation means suspended from the pistonlike means, a rotary drill rod comprising an elongated pipe having a longitudinally extending bore therethrough and an annular bit at the distal end thereof, the piston-like means being slidably received in the bore through the proximal end thereof and there being an annular shoulder about the periphery of the bore to receive blows from the hammer of the mechanism adjacent the bit, means defining an annular seat about the periphery of the bore between the shoulder and the mouth of the bit, which is of lesser inside diameter than that of the shoulder, the excavation means being slidably received in the distal end portion of the bore through the opening of the shoulder and having one end thereof engaged with the seat, fluid passage means in the rod extending generally longitudinally of the bore between a point adjacent the shoulder and a point about the periphery of the seat, and porting in the body of the bit, extending generally axially thereof between the fluid passage means and the working face of the bit at the distal end thereof, together forming a passage about the excavation means through which fluid can be released into the working face of the bit from a point adjacent the opposite end of the axcavation means, and means whereby the released fluid can discharge from the face of the bit toward the proximal end of the pipe on the opposite side of the pipe from the excavation means.
 2. The combination according to claim 1 wherein the shoulder is disposed on the pipe.
 3. The combination according to claim 1 wherein the excavation means takes the form of a core barrel.
 4. The combination according to claim 1 wherein the fluid passage means takes the form of fluting in the peripheral wall of the bore.
 5. The combination according to claim 1 wherein the bit is rigidly connected to the distal end of the pipe.
 6. The combination according to claim 1 further comprising attachment means on the proximal end of the piston-like means for releaseable engagement by a wire-line retriever or the like.
 7. The combination according to claim 1 wherein the excavation means is relatively rotatably engaged with the seat.
 8. The combination according to claim 1 wherein the excavation means is axially displaceable in relation to the piston-like means and yieldably biased into a stopped position relatively spaced therefrom.
 9. The combination according to claim 1 wherein the bit has a greater diameter than the pipe and the pipe forms the inner periphery of an annulus which is disposed between the pipe and the wall of the excavated hole, to discharge the released fluid therethrough.
 10. The combination according to claim 9 wherein the outer periphery of the bit is adapted so that the released fluid can pass thereacross to an annulus formed by the pipe and the wall of the excavated hole.
 11. The combination according to claim 1 wherein the hammer mechanism is fluid operated and there are fluid transmission means for operating the hammer mechanism including means for passing fluid through the piston-like means and means for exhausting the fluid into the fluid passage means after the mechanism has operated.
 12. The combination according to claim 11 further comprising means on the piston-like means for generating a pressure differential thereacross longitudinally of the bore, to maintain the hammer mechanism in operative relationship to the shoulder during the application of the blows.
 13. The combination according to claim 12 wherein the proximal end portion of the bore is operatively fluid pressurized and the pressure differential generating means is operative to cause a pressure drop across the piston-like means in the direction of the distal end of the bore.
 14. The combination according to claim 1 wherein the piston-like means also has an anvil suspended therefrom and the anvil is interprosed in the bore between the hammer and the shoulder to receive and transmit the blows to the shoulder.
 15. The combination according to claim 14 wherein the excavation means is suspended from the anvil.
 16. The combination according to claim 15 wherein the excavation means is axially and/or rotationally displaceable in relation to the anvil.
 17. The combination according to claim 14 wherein the hammer mechanism is fluid operated and there are fluid transmission means for operating the hammer mechanism including means for passing fluid through the piston-like means and means for exhausting the fluid into the fluid passage means after the mechanism has operated, and wherein the anvil defines a passage for the fluid and the fluid exhaust means is operative to exhaust the fluid through the anvil passage. 